Electric welding.



S. C. CARY.

ELECTRIC WELDING.

APPLICATION FILED FEB. 19. I917. 1,226,639. Patented May 22,1917.

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S. C. CARY.

ELECTRIC WELDING.

APPLICATION FILEDFEB. 19. 1917. 1,226,639. Patented May 22,1917.

4 SHEETS-SHEET 2- M anuewfoz S- C. CARY.

ELECTRIC WELDING. APPLICATION FILED FEB. 19. 1917.

Patented May 22, 1917.

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srENc ne. CARY, or BROOKLYN, NEW YORK.

ELECTRIC WELDING.

Specification of Letters Patent. Patented lIa 22, '7

' Application filed February 19, 1917. Serial No. 149,401.

To all whom it may concern:

Be it known that I, SPENCER don a citizen of the United States, residingat the city of -New York, borough of Brooklyn, county of Kings, andState of New York,

have invented a certain new and useful Electric-Welding, of which thefollowing is a specification.

In the art of welding thin metal, usually sheet iron and steel,difiiculty is experienced in the operation of uniting with a continuousseam and by electric heat and pressure the marginal portions of a metalsheet or the edge portions of twoadjacent sheets.

one cause of the difficulty is the variable resistance to the flow ofthe electric currentthrough the marginal overlapping portions, whichvariable resistance is brought about by a non-parallel condition of saidmar- !ginal portions so that when brought together thereis more of anoverlap at one side portion than at the opposite side portion of thesheet or sheets. This condition is encountered in electrically weldingthe fiat sheets of commerce, the edge portions of which frequently aremore or. less rough, but such condition is observable, moreparticularly, in electrically welding the marginal portions of a metalsheet which is bent to assume a hollow cross sectional form, as in themanufacture of cylindrical objects,like pipe. Experience shows that inbending a relatively wide sheet to a cylindrical form, the marginalportions of the sheet are unequally lapped, notwithstanding the factthat said marginal portions may have been out true prior to the bendingoperation; and when the electrical current is applied, such inequalityin the lap results in a variable resistance to the flow of the heatingcurrent, frequently resulting in an imperfectly welded seam.

According to one part of this invention, the sheet or sheets are firstpreliminarily positioned in the work holders, the marginal portions aretrimmed to bring them into parallelism, the marginal portions are thenbrought into overlapping relation so as to attain. uniformity in theextent or degree of the overlap throughout the width of the sheet orsheets, and electric heat is applied in conjunction with pressure tosecure the continuous seam by which the marginal portions are weldedtogether in a perfect manner. i

The mechanism for carrying out the operations herein briefly outlinedembodies a plurality of work holders adapted for retaining the marginalportions of a single sheet or the corresponding portions of a pluralityof sheets, one of said work holders being movable relatively to theother whereby the marginal portion confined in said movable work holderis brought into a definite overlapping relation to the other marginalportion.

In the machine disclosed herein, two pressure and current carryingelectrodes are employed, both of which may be movable in a definite pathrelatively to the work, as disclosed in my prior application Serial No.M5511; but it is preferred inthe machine of this application to employone stationary electrode and a rotatable electrode movable ina definiterelation to the stationary electrode, whereby the marginal portion ofthe metal retained in the work holders are adapted to be positionedacross the stationary electrode and in the proper overlapping order oneto the other so that when traversing movement is imparted to therotatable electrode the overlapped metal affords resistance uniformlythroughout the width of the sheet to the flow of the electrical currentfrom one electrode tothe other and through such overlapped mar gins, thetraversing movement of the rotatable electrode feeding currentprogressively to the overlapped margins and applying the requisitepressure to the metal rendered plastic by the heating efi'eet of the'current so as to. secure the desired uniformity in the seam by which themarginal portions ment is imparted to the traveler or carriage by theoperation of a screw and a nut, the I latter being guided by a suitabletraekwvay and being connected operatively by a thrust bar with saidtraveler or carriage, With as said electrode begins its traversingmovement in one direction and is thereby brought into contact with thematerial, the automatic switch is actuated to establish the flow ofcurrent during the welding operation, upon the completion of which saidswitch is again actuated to cut off the flow of current to theelectrodes whereby no current flows through the electrodes upon thereturn traversing movement of the rotatable electrode to its initialposition.

The relative positions of the work to the stationary electrode isdetermined primarily by gage mechanism, the latter being shiftable intooperative relation to said stationary electrode for the purpose ofinitially bringing the marginal portions of the metal into properrelation to each other, said gage mechanism being shiftable out ofposition so as to be out of the path of the rotatable electrode and freefrom electrical contact with either electrode during this weldingoperation. It is preferred to employ a gage member mounted-by slidingmovement in a hinged carrier, the same being swung on a horizontal axisso as to drop down out of the way after it shall have been used todetermine the relation of both marginal portions of the work within therespective work holders.

A salient feature of this invention consists of means operating upon themarginal portions of the work for bringing the same into parallelismwhereby in the subsequent operation prior to the application of weldingheat and pressure said parallel marginal portions are uniformly lappedand afford resistance uniformly to the flow of the electrical heatingcurrent.

Said means for securing parallelism in the marginal portions of the workmay be, and is preferably, embodied in the form of trimming mechanismadapted to be operated in embodied as a part of the gage mechanism so asto be shiftable therewith into and out of operative relation to the workholders upon thin metal, embodying this invention,

the welding mechanism being shown in the initial position.

Fig. 2 is a front elevation thereof.

Fig. 3 is a top plan view of" part of the machine illustrating theautomatic driving means and an automatic current cut-out adapted tocontrol the flow of current to the weldingmechanism.

Fig. 4 isa plan view, partly in horizontalsection, illustrating aplurality of workholders and a Work gage which is shiftable into and outof the path of the material to be operated upon by the weldingmechanism.

Fig. 5 is a vertical section through a part of the machine and the workgage mechanism, the movable element of the-work gage being shown inoperative position with respect to the stationary electrode.

Fig. 6 is a cross section through the gage mechanism and the stationaryelectrode shown in Fig. 5, illustrating the gage in the operation ofdetermining the initial positions of the marginal portions of the work.

Fig. 7 is a side elevation, partly in vertical section, illustrating apreferred embodiment of the invention, wherein a duplex trimmingmechanismis employed forthe purpose of cutting the marginal portions ofthe metal along the edges thereof in a manner to bring said edges intoparallelism prior to the action of the welding mechanism thereon, the

dotted lines illustrating the. out-of-service position of thework-gaging mechanism and the work-trimming mechanism.

Fig. 8 is a plan view of the work-gaging mechanism and the work-trimning mechanism shown in Fig. 7 the welding mechanism except thestationary electrode being omitted.

Fig. 9 is a cross section on the line 9.9 of Fig. 8,'illustrating thegaging mechanism and the trimming mechanism in position for operationupon the marginal portions of the work so as to bring the resultingedges of said marginal portions into parallelism prior to the operationof lapping the trimmed edges and prior, also, to the welding operationby which a continuous seam is obtained for joining said marginalportions of the metal in a satisfactory manner.

Fig. 10 is a detail sectional view of one form of spring pressuremechanism mounted on the reciprocating carriage for securing therequired mechanical pressure of the roller electrode upon the materialunder treatment.

as to rotate the feed screw in one direction or the other whereby theelectrode-supporting carriage may be reciprocated bypoweroperated'mechanism.

The welding mechanism embodies a plurality of electrodes A, B whichcooperate in applying electrical heat and mechanical pressure tothe-thin pieces of material composing the work, said electrodes beingmovable relatively one to the other, and at least one of said electrodesbeing a roller adapted to traverse the lapping marginal portions of thematerial in order to produce a continuous seam or weld, whereby saidmarginal portions are united in a way to produce'a seam or jointintegral with the metal, and said seam or weld is rolled by mechanicalpressure acting upon the plastic metal to reduce the seam or weldsubstantially to the thickness of the individual pieces composing thework, thus eliminating rough or irregular surfaces at the seam betweenthe pieces of metal.

' In the form of welding mechanism shown in the drawings I have electedto illustrate the same in connection with flat metal sheets, the samebeing united in end to end order So as to produce along continuous massof metal which may vary from one hundred to three hundred feet or morein length, but it will be distinctly understood that the invention isnot restricted to operation upon fiat 'metal, for the reason that theprinciple of the invention may be utilized in the treatment of metalcomposed of a thin sheet bent into cylindrical, tubular, or otherdesired form in cross section, and the edge portions of which metalsheet are to be united by a continuous seam.

The electrode A is preferably a flat elongated bar adapted to besupported in a stationary position in the machine, whereas electrode Bis a solid roller or diskmounted in a carriage for movement in arectilinear path and into contact with stationary electrode A, but inthis connection it is desired to state that the invention is not to be.re-

,stricted to a stationary electrode and a roller electrode movable intocontact therewith, for the reason that the welding mechanism may embodya plurality of cooperating rolls, substantially as disclosed in myapplication Serial No. 94,554 to which reference has 'been made. Thestationary electrode A consists of a single piece or bar composed ofcopper or other good electrical conduct-,

ing material, such 'bar being substantially rectangular 1n crosssection, as shown in Figs. 2 and 6, and the top edges of said bar beingbeveled at a, thus producing a narrow tread surface (1, intermediate thebeveled edges a. The width of the tread surface a is equal to orslightly exceeds the width of the resulting seam in the metal, whereasthe bar A is equal in length at least to the width of the material to beoperated upon. The bar A is seated in a recess 0 of a pillar C attachedrigidly toan arm C extending forwardly from the frame I) of the machine,said electrode bar A be- -ing retained in position by a clamping plate 0which is engaged by a bolt 0 secured in the arm C, whereby the electrodebar A is retained fixedly in a horizontal position, and said electrodemay readily be dismounted from the supporting arm C when occasiondemands.

The roller electrode B is composed of a mass of copper or other goodelectrical conducting material, the edge portions ofovhich are beveledat 7) so as to produce a tread surface b, the width of which is equalsubstantially to the width of the tread surface a of stationaryelectrode A, see Fig. 2. Said roller electrode is carried by an arbor I)which is mounted in any suitable way in bearings of a swinging arm I),said arm being forked or slotted as shown in Fig. 1 to permit the rollerelectrode to rotate freely within the slotted portion. The carrying armD is supported for pivotal movement .on a spindle (Z mounted independing lugs (Z of a carriage E. Said carriage is fitted snugly to theunder side of an overhanging zontal position over stationary electrodeA.

The arm F is provided at its lower edge with lateral flangesconstituting a track or guideway' for the carriage E, the respectiveside portions of which are provided with upstanding flanges c whichembrace the laterally extending flanges f, as shown in Fig. 2, wherebythe carriage is fitted slidably to the under side of the arm F. Saidcarriage is provided with upstanding bolts f on which are loosely fittedwear plates f which are pressed forcibly into contact with the uppersurfaces of the t ack flanges f by springs P which loosely encircle thebolts f, and the tension of which springs is adapted to be regulated byadjusting the nuts 7 on said bolts. The wear plates f and spring 7"?provide means for retaining the carriage E into close frictional contactwith the under-surface of the arm F, thus-compensating for wear due tothe frictional engagement of the moving part E with the stationary partF, but at the same time said carriage E is free to move in a rectilinearpath along the guideway afforded by the overhanging arm F so aS toimpart a traversmg movement to the roller electrode B.

Said roller electrode and the pivoted arm D are held normally in araisedposition by a spring G, see Fig. 1, the respective end portions ofwhich are attached to pivoted arm D and to depending lugs d of thecarriage, but the required mechanical pressure from the roller electrodeB to the material 7 under treatment is secured by plungers G, one ofwhich is shown in detail in Fig. 10.-

Said plungers G are positioned at the respective sides of carriage E(see Fig. 2), and are fitted sli'dably in guides 9 provided on saidcarriage. The plungers are pressed downwardly by the action of'springs gincased within the guides g, and said plungers are in contact at theirlower end portions with arms 9 which are rigid with the pivoted arm D.The plungers G and the spring G thus act in opposition to each other, asit were, in retaining the arm D and the roller electrode B normally inpre determined positions for said roller to have electrical andmechanical contact with the lapped marginal portions of the metal to beFor imparting the traversing movementto carriage E and roller electrodeB, I employ a feed screw I, a traveler J and a nut K, substantially asshown in Figs. 1 and 3.

Said traveler J is fitted for sliding move-.

ment 'in a horizontal path on guideway j forming a part of the machineframe D, and in order to connect the traveler J with carriage E, a baror link J is used, the

same being housed or contained within a chambered part of machine frameD, as indicated in dotted lines in Fig. 1, and the respective endportions of said link or bar J are connected pi-votally with traveler Jand carriage E. The traveler is provided with upstanding arms y" betweenwhich is fitted the nut K. Said nut is connected with the traveler J fora limited sliding movement between the upstanding arms j and,furthermore, the nut is provided with an axial threaded opening withwhich engages the threads of the feed screw I, whereby rotative movementof the feed screw imparts movement to the non-rotatable nut K, and thusthe movementof thenut is communicated to the traveler J. The feed screwI is unitary with a drive-shaft I journaled insuitable bearings providedon the machine frame D, and upon a gear housing D the latter beingfixedly attached to the rear part of the machine frame D. Upon thisgearhousing is positioned a motor L, the shaft of which is provided witha gear I that meshes with agear Z on a shaft L, the latter extendingwithin the gear housing D. .The shaft L drives a train of reversiillg Im on the motor driven shaft, and thus the. gears M M are normally drivenin opposite directions to each other by the shaft L, but, said gears M Mdo not communicate motion to the shaft I or the feed screw 1, exceptwhen one or the other of said gears M M are" made fast with said shaftI. The operation of making the gears M or M fast with the shaftI isaccomplished by a clutch N mounted on a shaft n in the gear housing Dsaid clutch N being positioned between the gears M M and adapted toengage with clutch faces provided on said gears or to be retained in aneutral position intermediate said gears. The means for operating theclutch is controllable in a way by the traversing movement of thetraveler J, but means are provided, also, for manually throwing theclutch into operative engagement with the gear M for the purpose ofstarting the machineinto operation. I

The clutch shaft 9t protrudes at one end beyond the gear housing, towhich protruding end is secured a lever O, the upper part of which isexpanded to form a cam-shaped head 0, the cam surfaces of which areoppositely inclined to each other, as shown in Fig. 1. The shipper leverO is adapted to be manually operated by a lever 10 mounted loosely onthe clutch shaft n. The upper part of this lever 10 is provided withlugs 11, 12 positioned at the respective sides of the shipper lever Oand adapted to engage therewith. The lower end of the lever 10 is formedwith a toe-piece 13 engaged by a latch 14 pivoted on the machine frameD, and to this latch isconnected a link 15, the lower end of which ispivoted to a bellcrank 16, the depending arm of said.

bellcrank being pivoted to a rod 17 which is pressed in one direction bya spring 18,

said rod being pivoted to a foot-treadle 19 positioned within convenientreach of the operator. stationed at the front of the machine. With thelatch 14 in engagement with the lever 10, the clutch is locked in aneutral position free from engagement with the gears M M, but when it isdesired to set the machine into operation the attendant presses atreadle 19 and withdraws latch 14 from lever 10, whereupon a spring 20presses a roller 21 forcibly against one cam surface of leverO, therebyturning the shaft 'feed screw is rotated in'one direction, so as to acton the nut K and impart traveling movement to the traveler J, 'wherebythe thrust bar J is actuated to impart movement to the carriage E andtraversing movement is thereby imparted to the roller electrode withrespect to the stationary electrode.

The clutch is automatically disengaged from gear M as the rollerelectrode reaches the limit of its movement over the stationaryelectrode, and this actionis brought about by an automatic stopmechanism now to be described;

22 designates a horizontal bar positioned intheupper part of the machineand intermediate the gear housing D and the rigid arm F, one end of saidhorizontal bar being pivotedtoa rocker 23 supported on the machineframe.- The other end of this horizontal bar is linked'to a rockshaft 24supported in a bracket 25 attached to the gear housing D said rockshaftbeing provided with a depending link 26, to the lower end of which ispivoted a bar 27, the other end i of which has a pin and slot connection28 with the lever O. Said horizontal bar 22 carries two stops 29, 30which are adjustably fastened to said bar 22, and with these stopscooperates a pin 31 (indicated in dotted lines in Fig.- t) attached toone of the arms oftraveler J, said pin 31 being positioned for movementbetween the stops 29, 30. As the traveler J moves forwardly under theaction of the screw the pin 31 approaches the stop 20, and when thereturnin traveler and the pin reach the limit of their forward movement,said pin strikes the stop 29 and imparts movement" to the bar 22, thelatter operating to rock the shaft 24 and swing the link 26 in adirection to impart movement to the bar 27, the operation of whichimparts rocking movement to the lever 0 so as-to turn the shaft 1 andthus.

shift 'thefclutch N from the -"gear M over to and into engagement withthegear M,

the result of which is to'reverse the dII'GC-V tion of rotation of thefeedstg'ew I. The screw now acts'on the nut' K to move the .travelerJ ina" reverse direction, thus drawing the carriage E and the rollerelectrode B backwardly over the welded seam, such reverse movementtaking place until the pin 31. strikes the other stop 30, whereupon thebar 22 and rockshaft 24, are operated to impart movement m a .revorsedirection'to the 'bar 27, and thusfretilifnfithe lever O to a. positionwherein-the clutch Nis free from engagement with. gears 'M orM,

stopping the operation of the -rnachine and the clutch ina. neutralposition,

the lever 10. into {position to be engaged y the latch 14 .Twhich actsto lock a lug on which is mounted the roller 21,

as shown in Fig. 1, said lever 32 and the spring 20 being yieldable tothe cam surfaces of the lever 0 when said lever is operated by manuallydepressing the treadle 19 or by the action of the automatic stops 29 and30.

Projecting forwardly from the machine frame are brackets 33, 34positioned at the respective sides of the arm C which carries thestationary electrode A. Bracket 33 carries or supports one of the twowork holders, said work holder on the bracket 33 being. indicated in itsentirety by the reference character P, whereas the other of the two workholders, Q, is carried by the bracket 34. Said work holder Q may be ofany approved construction, but as shown hereinit is adapted for thereception of metal in sheet form. Said work holder Q embodies a base 9and a pivoted clamp g, the latter being depressed upon the metal by theoperation of a cam lever gflsee Fig. 2. The work holder Q is stationarywith respect to electrode A. The other work holder P embodies a bedplate p,- a pivoted clamp p and a cam lever p similar in all respects tothe corresponding parts of work holder Q, but the bed plate p of workholder P is shiftable with respect to the work holder Q for a purposewhich will presently appear. Said work holder P is fitted for slidingmovement within a flanged foundation plate 35 fixedly attached tothebracket 33. Cooperating with the sliding bed plate 10 is an eccentrlc36, see dotted lines in Figs.- 2 and 4, the same being attached to ashaft 37 supported in a fixed bearing 38 of the foundation plate 35, andto the lower end of this shaft is attached an operating lever 39,whereby the cam may be manually rotated for the purpose of advancing thework holder P to- Ward the work holder Q in" order to position I themarginal portions of the metal in lapping relation over stationaryelectrode A.

It will be understood that the machine of this invention is adapted foroperating upon sheets are to be positionedin lapping relation and intocontact withthe stationary v electrode A so as-to be operated 'upon bythe traversing electrode B. Subsequent to the introduction of the sheetor sheets within the work holders, the marginal portions of said sheetor sheets are initially positioned by gaging devices in accuraterelation to the stationary electrode, and I will now proceed to describeone practical form of gage mechanism which may be used for the purposementioned.

On the front end of the machine, and below the stationary electrode issupported a horizontal arbor 40, the latter being fixedly attached tothe brackets 33, 34, and serving as a means for tying the same together,this function being performed, also, by the tie rod 41, see Fig. 2.Mounted loosely on the arbor is a carrier 42 constituting one element ofthe gage device, the other element of which gage device is a sliding bar43.

The carrier 42 is provided with a guideway' '44 in which is slidablyfitted the gage bar 43, the latter being provided on its outer end witha hand-grip45, see Fig. 5. The

. sliding gage member orbar 43 is provided on its under side with agroove 46, which grooved part of the gage bar is adapted to fit thebeveled and track surfaces 0, a of.

electrode A. when the gage is in the operative position shown in Figs. 5and 6. The gage is provided on its uppersurface with an upstandingshoulder 47, the latter being positioned intermediate two upper surfacesof the gage, which two surfaces are in different horizontal planes, seeFig. 6. The carrier is adapted to swing on a horizontal axis afforded bythe arbor 40, so that the carrier may be dropped down to theout-of-service position shown in Fig. 2, but it is apparent that thecarrier may be swung in an upward direction to assume the operativeposition illustrated in Fig. 5, in which operative position the carrieris retained by a latch 48, the same being pivoted on the carrier andcontrolled by a spring 49, the end of the latch 48 being adapted forlocking engagement with a keeper plate 50 fixed to the bracket 33 andpositioned in the path of the latch 48 when the carrieris swung upwardlyinto the operative position.

In using the gage mechanism the carrier is swung on the arbor 40 to theraised position of Fig. 5, the latch 48 snapping into engagement withthe keeper plate 50. The operator now presses the gage bar 43 inwardlyso as to slide it lengthwise of. the carrier 42, which inward slidingmovement of the gage bar brings the grooved portion 46 into contact withthe top portion of electrode A. Thegage-bar is thus positionedintermediate the inner approximate ends of work holders P Q,-whereby thestop shoulder 47 of the gage bar is in the path of the marginal portionsof the 'materi'al. With the clamps'p q of work holders P Q, re-

spectively, in raised positions, the work can be adjusted within theholders so that the marginal-portions X X of the work are adapted to bepositioned upon the two surfaces of the gage bar 43 and into contactwith the stop shoulder 47, the gage bar and its shoulder thus serving toinitially position the'marginal portions X X of the work in accuraterelation to the electrode A and at a time when the roller electrode B iswithdrawn from the path of the material, as shown in Figs l and 4. Theoperator should now manipulate levers p 9 in order that clamps p, 9 maygrip the work and retain the same fixedly in position within the workholders whereupon the gage bar should be pulled outwardly and away fromcontact with the marginal portions of the material, so that the latch 48may be released and the entire gage device dropped down into theout-of-service position of Fig. 2. The position of the marginal portionsof the material-having been accurately determined, the next-step in theoperation consists in bringing said marginal portions intolappinggcontact, and this is effected by moving the lever 39 to impartrotative movement to cam 36, the latter acting to advance the workholder P and the material X, so that the material X will lap thematerial X over the electrode A. The work is thus adapted .to be heldfirmly bythe two holders and to be accurately positionedwith respect toelectrode A. It should be stated that prior to introducing the work intothe machine and gripp ng said work by the holders P Q, the

margmal'portions of the material should be sandrblasted', as disclosedin my application Serial No. 89289, whereby the surface oxidation orscale is removed from the marginal portions of the work, which marginalportions are to be brought into lapping con- .tact and electricallywelded by the application of electric heat so as to render the metalplastic, and by the application of-mechanical pressure to effect thecontinuous seam which unites said marginal portions of the material.

I will now proceed to describe the, trimming mechanism by which theadjacent marginal portions are adapted to be cut or trimmed on parallellines subsequent to the mechanism is shiftable with the gage mechanisminto and out of operative relation to the electrodeA and to the marginalportions of the material.

Referring now more particularly to Figs.

7, 8 and 9 of the drawings, the electrode A and the gage carrler 42 aresimilar to the devices heretofore described, but in this embodiment ofthe invention it is preferred to employ a gage bar 43 whichissomewhatwider than the gage bar 42, heretofore described and illustrated inFigs. 5 and 6. The

wide gage bar is provided'with a longitudisides of this bar arefittedthe blades 53, 54,

the same being bolted firmly'to the cutterhead. The blades'run'parallelof the cutterhead and they are adapted to shear past the edges of theslot 51 in the gage member, see Fig. 9. The cutterhead is forked at oneend, as at 55, and it is pivotally mounted on lugs or bearings 56extending upwardly from the gage member 43, for which purpose the forkedend of the'cutterhead is attached to a horizontal rockshaft 57 Aroundthis 'rockshaft is coiled a spring 58 which tends to normally lift thecutterhead in order to free the blades 53, 54 from the slot 51 of thegage member, thus allowing the material X X to be readily introducedover the gage 43 and into contact with the stop 47 Suitable means areprovided for manually operating the cutterhead 52, but as shown moreparticularly in Fig. 7, said means are treadle-operated by the followingmechanism 1- An armv58 is attached rigidly to the rockshaft, the lowerend of said arm being connected to a link, 59,- the other end of whichlink is pivoted to a rocker arm 60 fitted loosely on arbor 40, supportedas heretofore described on the machine frame or upon the brackets 33, 34thereof. This rocker arm 60 is provided with a lug 62 which ispositioned in cooperative relation to a lug 63 forming a part of an arm64 which is fitted loosely on arbor. 40. To the free end of the arm 64is'pivoted the upper end of rod65', the latter being impelled normallyin an upward direction by a spring 66; I Said rod passes loosely througha guide 67, and thelower end of the rod is attached to the treadle 68.The trimming mechanism is thus attached to or mounted on the shiftablemember 43 of the gage, and said trimming I mechanism is shiftable withthe carrier 42 when the latter is moved into or out of theout-of-service position, the link 59 permite cutterhead 52 with the gagemechanism when the carrier 42 is swung on the horizontal axis affordedby the arbor 40.

It is apparent that the movement of the carrier 42 inan u'pwarddirection can take place freely,.for the reason that'the arms 60, 64 andlink 59 permit of such movement.

When elevated and held by the latch 48 the 1 carrier presents the gagemember 43 into position for, movement over electrode .A, which movementis readily effected by the operator applying pressure to the hand-grip45. The gage may thus slide over the elec-v trode, and in this operationthe cutting mechanism is movable with the gage, but the spring 58retains the pivoted cutterhead in the raised-position shown in so thatthe material X X 'can bemovedfi over and into contact with'the gage,whereby: the material will be positioned by the stop.

47 into proper relation to the electrode A. The operator now appliespressureLtofgthe treadle 68 so as to turn the arm 64 and its shoulder 63into contact with the s'hoiilder 62 of the arm 60, whereby the arm 60 isrocked to impart movement to link 59 and;

arm 58 in a manner to depress the cutterhead 52 and cause the knives 53,54 to shear the marginal portions of the material X X,

as a result of which the adjacent edges of said marginal portions arebrought into parallelism. Upon removing pressure from the treadle 68,the spring58 lifts the cutterhead clear of the gage, after which themember 43 is withdrawn, the latch 48.is released and the carrier and thetrimming. mechanism are dropped to the outof-service positions. Thematerial which is held in one work-holder, as P, is now manipulated tobring the trimmed edge of said material into lapping contact with theother trimmed edge of the material, and for this purpose it is onlynecessary to impart the required sliding movement to the work-holder P,the

extent of the sliding movement being dewhich are effective in removingrough edges from the material and operating to secure parallelismbetween the trimmed edges of the marginal portions X X, whereby themarginal portions are adapted to be overlapped to an equal extentthroughout the width of the sheet or sheets of material, as a result ofwhich the equally lapping portions of the material offer resistanceuniformly to the flow of the welding current at all points in thetraverse of electrode B relatively to the lapped margins of material.

The machine disclosed herein embodies a transformer positioned within achambered part of the main frame D, wherebythe weight of saidtransformer is not imposed upon the movable part of the machine, such asthe element which carries the movable electrode and which is one of thecharacteristic features of a prior application Serlal No. 123,269, thetitle to which, and to the terminal connected with the carriage for themovable electrode B, whereas the other terminal includes the stationaryelectrode A, whereby current is supplied to the electrodes A,-B for thepurpose of rendering plastic the metal which it is desired to weld by acontinuous seam. The electrical equipment shown includes a controlling,solenoid 7 2 and switches" 7 3, 74 actuated substantially in the mannerdisclosed insaid application Serial No. 123,269. The flow of current tothe electrodes is dependent upon the contact of roller electrode B withthe, lapped portions 1 of the metal, and upon the operation of a cut-outS shown in Fig. 1. This cut-out comprises a stationary contact 75 and amovable contact 76, the latter being on a vibratory arm 7 7 under thecontrol of a spring 78. Cooperating with the vibratory arm is a detent79 which is normally in engagement with a movable detent 81 carried by avibratory arm 82 under the control of a spring 83, and adapted to bearrested in a normal position by the stop 84. The vibratory arm 82 is inthe form of a bellcrank, one end of which is engaged by a latch 85,which cooperates with stops-86, 87 carried on a shiftable bar 88. Oneend of this shiftable bar 89 of the carrier E, said arm extendingupwardly through a slot in the overhanging rigid arm F, but the otherend of the horizontal bar 88 is pivoted to the forward arm 9' oftraveler J. In the normal position of the cut-out the spring '83 holdsthe detent 81 into contact with the detent 79, thus locking thevibratory arm 77 for the contact 76 to be free from the contact 75, andfrom these contacts 75, 76 run conductors 90, 91 leading to the solenoidand the switches so as to prevent the flow of current to the electrodesA B in the normal position of the mechanism. Asthe electrode B makescontact with the lapped marginal portions of A the metal, the stop 86 iscarried by the forward movement of the traveler-away from the latch 85,so that the vibratory arm 77 will be operated to move the contact 76into electrical engagement with contact 75, and thus establish the flowof current to electrodes A B, the effect of which is to-render plasticthe metal under treatment, and as the electrode B traverses the metaland the electrode A, the metal is pressed together and welded to producethe continuous seam. By the time that the electrode B completes itsforward movement, the stop 87 actuates the arm 82 so as to restore thedetent into contact with the member 79 and separate the contact 76 fromcontact 75, breaking the circuit on the return movement of the electrodeB to its initial position.

It is thought that the operation of the invention will be understoodfrom the foregoing description, but it may be summarized aresand-blasted, as heretofore described, in

order to remove the surface oxidation and scale. When operating uponflat metal sheets, the marginal portion of one sheetis introduced intoholder P, .and a marginal portion of another sheet is introduced intoholder Q, but should the mechanism be desired for operation upon tubularsheets, the respective edge portions thereof are introduced into the twoholders P Q. The gage is used to initially determine the relativepositions of the marginal portions of the metal, and the trimmingmechanism is operated to shear off the adjacent edges of the margins,thereby removing any rough edges and bringing said edges intoparallelism, after which the gage and trimming mechanism are moved tothe out-of-service position. The holder P is now moved toward the holderQ, until the trimmed edges are in contact, and as the edges are parallelit follows that the marginal portions are lapped to a uniform extentthroughout the width of the sheet or sheets, whereby said marginalportions ofi'er resistance uniformly to the flow'of the welding current.The operator presses upon treadle 19 and the motor actuates' to impartthe traversing movement to roller electrode B, current being supplied tosaid electrode B and the electrode A to render the metal plastic. Theroller electrode travels between the work holders and over electrode Ato effect the welding progressively, for the reason that the metal isrcn' dered plastic as the roller passes along said metal, and saidroller cooperates with electrode A in applying the pressure required toeffect the union of the marginal portions of the metal, as a result ofwhich a continuous seam is produced which affords a satisfactory unionbetween the marginal portions, the application of pressure rolling themetal along the seam down to the gage of the individual pieces composingthe sheets, in case two sheets are Welded in the manner described. Asthe roller electrode reaches the limit of its movement, the cut-outoperates to preclude the flow of current, and the driving mechanism thenbecomes effective in imparting reverse motion to the carriage and to theroller electrode so as to return said parts to their initial positions.

It should be mentioned that provision is made for supplying a coolingmedium to the pivoted arm D which carries the roller electrode and tothearm C, which supports the stationary electrode, for which purpose watercirculating pipes 92 are "attached to the proper parts, as clearly shownin Figs. 1 and 4.

- The machine disclosed herein produces continuous seams or weldsbetween the metal, and operates rapidly upon the metal so as to attainlarge capacity for the performance of the required work. By removing thetransformer from the carriage of the roller electrode, the weight of themoving parts is minimized, whereby the means or imparting reciprocating.IIlOtlO'IlftO thefar riage can be and is speedediupto'secure-thedesired? rapidity of op'eration, all of the required operations beingautomatic except those necessary to start the machine into service andto introduce and remove the material.

It will be noted that the feed nut isheld from rotative movement by thetraveler and that said feed nut has a limited lostmotion with respect tothe traveler. This is desirable in overcoming the inertia of the movingparts at the periods of time when the direction of rotation of the feedscrewis reversed so as to effect/the back and forth movements of theelectrode-supporting carriage.

The improvement in theart of electric welding thin metal herein shownanddescribed is not claimed herein for the reason that such improvementin the art forms the subject matter of a divisional, application filedMarch 31, 1917, Serial No. 158,814.

Having thus fully described the invention, what I claim as new, anddesire-to secure by Letters Patent is 1. In an electric welder, thecombination with a plurality of work holders, of means for trimming themarginal portions of thin metal to secure parallelism in the resultingedges, said trimming means being operable subsequently to the operationof positioning the thin metal in the work-holders, means for effecting arelative movement between said marglnal portions whereby they arepositioned in lapping contact, and means for electrically welding themarginal portions of said thin metal.

2. In an electric welder, the, combination with a plurality of workholders, of means for trimming the marginal portions of thin metal tosecure parallelism in theresulting edges, said trimming means beingoperable subsequently to the operation of positioning the thin metal inthe work-holders, and means fo moving one work holder relatively to theother whereby subsequent to the trimming operation the-marginal portionsofthe work are positioned into lapping contact, and means forelectrically welding the marginal portions of said thin metal.

3. In an electricwelder, the combination with a plurality of workholders, of means for determining the initial positions of the marginalportions of thin metal, means for trimming said marginal portions andthereby bring the resulting edges into parallelism, said trnnming meansbeing operable subsequently to the operation of positioning the thinmetal in the work-holders, and means for effecting a relative movementbetween the marginal portions subsequent to the trimming operationwhereby the trimmed marginal portions are positioned into lappingcontact, and means for electrically welding the marginal portions ofsaid thin metal.

4:. In an electric welder, the combination witha plurality of workholders, of means for determiningthe initial positions of the marginalportionsof thin metal, means for trimming said marginal portions andthereby bring the resulting edges into parallelism, and means for movingone work holder relatively to the other for a predetermined distance andsubsequently tothe trimming operation whereby the trimmed marginalportions. are positioned into uniform lapping contact. 4

5. In an electric welder, the combination with a plurality of workholders, of workgaging means for determining the initial positions ofthemarginal portions of thin metal, welding mechanism, said work-gagingmeans being shiftable relatively to said welding mechanism, and worktrimming means operable upon said marginal portions for'bringing theminto parallelism prior to the action of the welding mechanism 6. In anelectric welder, the combination with a plurality of work holders, ofmeans for initially determining the position of the work with referenceto the respective work holders, means operable simultaneously upon thecontiguous "marginal portions of the work to trim the same and therebysecure parallelism between said marginal portions, and welding means forsecuring the desired union between said trimmed marginal portions.

7. In an electric welder, the combination with a plurality of workholders, of means for initially determining the position of the workwith reference to the respective work holders, means operable upon themarginal portions of the work subsequently to the initial positioningthereof for trimming said marginal portions and thereby secureparallelism between the edges of said marginal portions, means forefiecting lapping contact between the trimmed marginal portions, andwelding mechanism for securing the desired union between said marginalportions. n

8. In an electric welder, thecombination with a plurality of workholders for retaining the marginal portions of the work in definiterelation to each other, gaging means tions of said marginal portions,means operable subsequently to the initial positioning of said marginalportions for securing parallelism between the edges thereof, means foreffecting lapping contact between said marginal portions, and weldingmechanism whereby the desired union is secured between the marginalportions of the material.

9. In an electric welder, the combination with a plurality of workholders for retaining the marginal portions of the work in definiterelation to each other, of trimming means operable upon themarginalportions of the work for securing parallelism between the edges thereof,means for efl'ecting lapping contact between the trimmed marginalportions of the work, and welding means for securing the desired unionbetween said trimmed marginal portions.

10. In an electric welder, the combination with a plurality of workholders for retaining the marginal portions of the work in definiterelation to each other, of gaging means for initially determining therelative positions of the marginal portions, said gaging means beingshiftable into and-out of operative position with reference to the workholders, trimming means operable upon the mar 'nal portions of the workfor securing para lelism between the edges thereof, said trimming meansbeing shiftable in unison with the gaging means, means for effectinglapping contact between the trimmed marginal portions, and welding meansfor securing the desired union between said lapped marginal portions ofthe work.

11. In an electric welder, the combination with a plurality of workholders for. retaining the marginal portions of the work in definiterelation to each other, of gaging means for initially determining therelative positions of the marginal portions, said gaging means beingshiftable into and out of operative position with reference to the workholders, trimming means operable upon the marginal portions'of the workfor securing parallelism between the edges thereof, said trimming meansbeing carried by the gaging means and shiftable therewith into and outof operative relation to the work, means for effecting lapping con" tactbetween the marginal portions, and atraversing electrical welding devicemovable in a definite path with respect to the lapped marginal portionsfor uniting the same with a continuous seam.

12. In a electric welder, the combinationv tive positions of themarginal portions, said gaging means being shiftaBle into and out ofoperative position with reference to the Work holders, trimming meansoperable upon the marginal portions of the work for securing parallelismbetween the edges thereof, said trimming means beingshiftable in unisonwith the gaging means, means for moving one work holder relatively totheother for effecting lapping contact between said trimmed marginalportions, and

a traversing welding device operable for i applying electrical heat andmechanical pressure to the lappedmarginal portions and unite the same bya continuous seam.

13. In an electric welder, the combina- 7 tion of a roller electrode, arelatively sta tionary electrode cooperating, with said rollerelectrode, a carriage on which the roller electrode is mounted, a feedscrew, a

traveler separate from said'carriage, a feed the other guideway, meansconnecting the traveler and the carriage for impa ting movement to thelatter from the former, a plurality of cooperating electrodes one ofwhich is supported by the carriage,ea feed 7 "nut movable with thetraveler, a feed screw,

and a reversible driving mechanism for'imparting rotative movement tosaid Jfeed screw. v v I 15. In an electric welder, a plurality of.separate guideways, a carriage slidableilon one of said guideways, atraveler slidable on the other guideway', means connecting the travelerand the carriage for imparting movement to the latter from the former, aplurality of cooperating electrodes one of which is supportedby thecarriage,vpre$ure means for efi'ecting a relativemovement -.between saidelectrodes whereby mechanical pressure is applied to the metal undertreatment during a traversing movement of the carriage, and meansractingupon the traveler for imparting reciprocating movement to said travelerand carriage.

16. In anelectric welder, aplurality of separate guideways, a carriageslidable on one of said guideways, a-.traveler slidable on the otherguideway, ;neans connecting the traveler and the carriage for'impartingmovement to the latterv from the former, a plurality of cooperatingelectrodes one of which is supported by the carriage, a feed nut heldfrom rotative movement by the traveler and movable therewith, a-feedscrew,

a reversible driving mechanism for impartmg rotatlve movement to saldfeed screw,

, and means operable-by the movement of the traveler for controlling thereversible driving mechanism.

17. In an electric welder, the combination with a carriage, and aplurality of electrodes at least one of which is supported limited lostmotion relatively to the traveler,a feed screw, and means for impartsing rotative movement to the feed screw.

18. In an electric welder,the combination with a trackway, of a carriageslidable relatively thereto, a spring-actuated arm pivoted to saidcarriage and movable therewith, a plurality of electrodes at least oneof which is mounted in said arm and held thereby 'in cooperativerelation to the other electrode, and means for imparting reciprocatingmovement to said carriage.

19. In an electric welder, the combination with a trackway, of acarriage slidable relatively thereto, an arm pivoted to said carriage,pressure'means mounted on the carriage and cooperating with the arm foryieldably forcing the sa me in one direction, a stationary electrodepositioned parallel to the path of .the carriage, a roller elec trodemounted in the pivoted arm and adapted to be yieldablypresented therebyinto cooperative relation to the stationary electrode, and means forimparting traversing movement to said carriage.

20. In an electric welder, the combination with a relatively stationaryelectrode, and a trackway positioned in parallel relation thereto, of acarriage in under running contact with said trackway, means forretaining said carriage in sliding contact with 'said trackway, meansfor imparting reciprocating movement to said carriage, an arm pivoted tothe carriage and movable therewith, a roller electrode mounted forrotative movement in said arm and movable with the carriage so as topartake of a traversing movement relatively to the stationary electrode,and pressure means operatively related to said pivoted arm wherebymechanical pressure is applied by the 00- operating electrodes to themetal under treatment during the traversing movement imparted to theroller electrode.

21. In an electric welder, the combination with a relatively stationaryelectrode, of a trackway in overhanging relation thereto, a carriageslidably fitted, to said trackway, an, arm pivoted to said carnage, saidarm be ng forked, a roller electrode positioned within the forkedportion of the arm and mounted in the arm for rotation-freely therein,pressure means carried by the: carriage and cooperating with said armfor pressing the roller electrode toward the stationary electrode, andmeans for imparting traversing movement to said carriage.

22. In an electric welder, the combination with a relatively stationaryanvil electrode, and a trackway adjacent thereto, of a a rriage fittedtosaid trackway for sliding movement thereon, a movable member mounted onthe carriage, a roller electrode supported by said movable member andmovable therewith relatively to said carriage, pressure means mounted onthe -arriage and cooperating with the movable member for effecting therequired pressure upon the material under treatment between saidelectrodes whereby the material is rolled to gage, and means forimparting a traversing movement to said carriage.

23. In an electric welder, the combination with a plurality of workholders, and welding mechanism, of a gage mechanism shiftable into andout of cotiperative. relation to said work holders, said gage mechanismembodying two movable'members one ofwhieh is adapted to be positionedbetween said work holders.

24:. In an electric welder, the combination with a plurality of workholders, and \veld ing mechanism, of a gage mechanism embodying aswinging member and a slidable member carried by the swinging member,said slidable member being adapted to be interposed intermediate saidwork holders.

25. In an electric welder, the combination with a. plurality of workholders, and welding mechanism, of a gage carrier mounted for movementinto an out of service relation to the welding mechanism, and a gagemember connected with the gage carrier for movement therewith, said gagemember being movable relatively to the gage carrier for interpositionintermediate the work holders.

26. In an electric welder, the combination with aplurality of workholders, and welding mechanism, of a gage carrier mounted for movementinto an out ofservice relation to the welding mechanism, means forlocking the gage carrier in operative position, and a gage membermounted on the. gage carrier and movable into position intermediate saidwork holders.

27. In an electric welder, the-combination with a stationary electrode,and a plurality of work holders, of a gage member movable into positionover said stationary electrode and intermediate the work holders.

28. In an electric welder, the combination with a'stationary electrode,and a plurality of work holders, of a gage member movable into positionover said stationary electrode and intermediate the work holders, saidgage tioned in the path of the marginal portions of the'work adapted tobe held in said work holders and operating to initially determine therelative positions of said marginal portions.

- gina l portions of the material to be united.

30. In an electric welder, the combination with a stationary electrode,and a plurality of work holders, of a gage member movable into positionover said stationary electrode and intermediate the work holders, saidgage member beingprovided with exposed surfaces with which are adaptedto contact the marginal portions of the material to be welded andprovided also with a stop member positioned intermediate said exposedsurfaces so as to have contact edge wise with said marginal portions.

31. In an electric welder, the combination with a stationary electrode,and a plurality of work holders, of a gage carrier hinged.

for movement on a horizontal axis, and a gage member slidably connectedwith said gage carrier, said gage member being movable over theelectrode and to a positlon intermediate said work holders.

32. In anelectric welder, the combination with a stationary electrode,and a plurality of work holders, of a movable gage carrier, and aslidable gage member sup-. ported by the gage carrier,-- said gage member-being movable into contact ,with said electrode and toa positionintermediate the work holders.

7 33. .I'n an electric welder, the combination witha stationaryelectrode, and a plurality'of work holders, of a gage carrier theaxisofmovement of which is in a difierent plane from the surface of theelectrode, and

' E-and movable" therewith, said Bo b eing' movable with respect to thegage car a gage member supported in the gage carrier age member QJr-ier]and to an operative position intermejdidtef'fsaid; work 1 holders.

"34. In an electricfwelder, the combination t i n ryelectrode, and a P Qholders, f gage arrier hinged I .for movement on a horizontal axis, anda gage member connected to-said carrier for sliding movement withreference thereto,

said gage member being movable into contact with-said electrode and tolposition intermediate' said Work'hol ders- I 35% In an'electric'welder, the combination witha stationary electrode, and aplurality of work holders, of a gage carrier hinged fol movement on ahorizontal axis, a latch for retaining the gage carrier in a fixedrelation to the work holders, and a gage member slidable upon the gagecarrier and mov- 36. In an electric Welder, the combination with astationary electrode and a plurality of work holders, of a gage carriermovable relatively to said work holders, and a gage member supported bythe carrier and movable to a position intermediate the work holders,said gage carrier being provided with two exposed surfaces in differentlevels and upon which the marginal portions of the material are adaptedto rest.

37. In an electric welder, the combination with a stationary electrodeand a plurality of work holders, of a' gage carrier movable relativelyto said work holders, a gage member supported by the carrier and movableto a position intermediate the work holders, said gage carrier beingprovided with two exposed surfaces in different levels and upon whichthe marginal portions of the material are adapted to rest, and means formoving one work holder relatively to the other, whereby upon thewithdrawal of the gage member the marginal portion in the movable workholder is positioned into lapping contact with the marginal portion inthe other work holder. 1

38. In an electric Welder, the combination with a stationary electrodeand a plurality of work holders, of a gage carrier movable relatively tosaid work holders, and a gage member supported by the carrier andmovable relatively thereto so as to assume an operative positionintermediate the work holders, said gage member being provided membermovable into an operative position mtermediate said work holders, atrimmingv mechanism carried by said gage member,

means 'for operating said trimming mechanism independently of themovement of the gage member whereby the trimming mechanism is effectivein bringing the edges of the marginal portions of the material intoparallelism-prior to the welding operation, and means for weldin thetrimmed edges of said marginal portions.

40. In an electric welder, the combination with a plurality of workholders, of a gage member movable into an operative positionintermediate said work holders, and a worktrimming mechanism carried bysaid gage member, said work-trimming mechanism being operableindependently of its movement with the gage member. a,

*1. In an electric welder, the combination able into contact with saidelectrode and to a position intermediate the work holders.

42. In an electric welder, the combination with a plurality of workholders, of a gage I member movable into an operative positionintermediate sald work holders, a cutterhead v mounted upon the gagemember, a'plurality of cutters attached to the'cutterhead, means forliftingthe cutterhead relatively to; the gage member so as to permlt themarginal portions of the material to be positioned by' the gage member,and means for operating said cutterhead.

43. In an electric welder, the combination with an anvil electrode, anda plurality of work holders, of aslotted gage member movable intocontact with said anvil electrode and to an' operative positionintermediate the work holders, a cutterhead attached to the gage memberand movable therewith, means for retaining the cutterhead in suchrelation to the gage member as to permit the free adjustment of the workinto contact with said gage member, cutters on the cutterhead adapted toshearthe metal, and means for operating the cutterhead.

44.- In an electric welder, the combination with a plurality of Workholders, of a gage carrier movable relatively to the work holders, agage member supported by the carrier and movable with respect to thework holders, cutting mechanism supported by the gage member and movablewith said gage member and the carrier, and operating means for impartingmovement to said cutting mechanism.

45. In an electric welder, the combination with a plurality of workholders, of a gage carrier movable relatively to the work holders, agage member supported by the carrier and movable with respect to thework holders, cutting mechanism supported by the gage member and movablewith said gage member and the carrier, and operating means effective inimparting movement to said cutterhead when the gage member is inoperative position with reference to the work holders, said operatingmeansbeing shiftable with the cutterhead when the gage carrier is movedinto an out-of-service position.

46. In an electric welder, the combination with a plurality of workholders, of a gage carrier movable relatively to the work hold ers, agage member supported by the carrier and movable with respect to thework holders, cutting mechanism pivoted to said gage member, andtreadle-operated means for imparting movement to said cutting mechanism,said treadle operated means including connections whereby free movementof the gage carrier is assured when shifting it to and from anoperativeposition.

47. In an electric welder, the combination with a stationary electrode,and a traveling carriage, of a roller electrode supported by thecarriage and movable into cooperative relation to said stationaryelectrode, means for feeding current to said electrodes, and meansresponsive to the movement of the carriage for controlling the How ofcurrent to the electrodes during the traversing movement of the rollerelectrode in one direction and for cutting off the fio'wof current asthe roller electrode travels in the opposite direc- SPENCER O. GARY.

